Lactose intolerance

Lactose is a type of sugar found in milk and other dairy products. An enzyme called lactase is needed by the body to digest lactose.

Lactose intolerance develops when the small intestine does not make enough of this enzyme.

The digestive system organs in the abdominal cavity include the liver, gallbladder, stomach, small intestine and large intestine.

Causes

Babies' bodies make the lactase enzyme so they can digest milk, including breast milk.

Babies born too early (premature) sometimes have lactose intolerance.

Children who were born at full term often do not show signs of the problem before they are 3 years old.

Lactose intolerance is very common in adults. It is rarely dangerous. About 30 million American adults have some degree of lactose intolerance by age 20.

In white people, lactose intolerance often develops in children older than age 5. This is the age when our bodies may stop making lactase.

In African Americans, the problem can occur as early as age 2.

The condition is very common among adults with Asian, African, or Native American heritage.

It is less common in people of northern or western European background, but still may occur.

An illness that involves or injures your small intestine may cause less of the lactase enzyme to be made. Treatment of these illnesses may improve the symptoms of lactose intolerance. These may include:

Surgery of the small intestine

Infections in the small intestine (this is most often seen in children)

Treatment

Cutting down your intake of milk products that contain lactose from your diet most often eases symptoms. Also look at food labels for hidden sources of lactose in nonmilk products (including some beers) and avoid these.

Most people with low lactase level can drink up to one half cup of milk at one time (2 to 4 ounces or 60 to 120 milliliters) without having symptoms. Larger servings (more than 8 ounces or 240 mL) may cause problems for people with the deficiency.

Milk products that may be easier to digest include:

Buttermilk and cheeses (these foods contain less lactose than milk)

Fermented milk products, such as yogurt

Goat's milk

Ice cream, milkshakes, and aged or hard cheeses

Lactose-free milk and milk products

Lactase-treated cow's milk for older children and adults

Soy formulas for infants younger than 2 years

Soy or rice milk for toddlers

You can add lactase enzymes to regular milk. You can also take these enzymes as capsules or chewable tablets. There are also many lactose-free dairy products available.

Not having milk and other dairy products in your diet can lead to a shortage of calcium, vitamin D, riboflavin, and protein. You need 1,000 to 1,500 mg of calcium each day depending on your age and gender. Some things you can do to get more calcium in your diet are:

Take calcium supplements with Vitamin D. Talk to your health care provider about which ones to choose.